Photographic Measurements Research Articles

Photoanthropometric study: are non-professional photographs suitable for objective and reliable analysis of facial features?

The face has been widely investigated using professionally taken frontal and lateral photographs, however, there is a lack of studies of non-professional facial photographs. It is not known if they could be suitable for facial analysis. The analysis of non-professional photographs could allow the performance of cost- effective longitudinal studies. To determine if non-professional photographs could be used for a reliable analysis of facial features. The frontal profiles of 18-21-year-olds (35 males, 39 females) were measured by direct anthropometry, in addition, professional photographs were taken and non-professional photographs were obtained. Anthropometric landmarks were superimposed on those photographs. The indices calculated on the basis of the measurements of direct anthropometry and both types of photographs were compared. The comparison of the measurements of direct anthropometry and professional photographs showed no difference between 14 out of 25 male and 10 out of 25 female facial indices (p > 0.05) after comparing the results of direct anthropometry with those of non-professional photographs, no difference was found in 8 out of 25 male and 7 out of 25 female indices. These indices were mostly composed of vertical parameters and eye measurements. Vertical facial dimensions and eye measurements may not only be used interchangeably for both facial photographs and direct anthropometry, but may also be suitable for objective and reliable facial analyses.

Digital improvements in the design and construction process of classical Chinese garden rockeries: a study based on material digitization

Rockeries have a complex and significant role in classical Chinese garden designs. They present distinct artistic characteristics and spatial hierarchies and are crucial to garden heritage conservation. Craftsmanship in rockery construction is a significant part of China’s intangible cultural heritage. Rockeries are primarily composed of naturally occurring rocks chosen for their uniqueness and complex shapes and textures. These rocks present challenges as nonstandard elements within the traditional Chinese garden context, as it is not easy to depict them using conventional blueprints and models. This complicates the design, adjustment, display, and construction of rockeries, which lacks tangible bases for reference. Consequently, the preservation and restoration of garden rockeries is difficult, and the perpetuation and dissemination of rockery construction skills face numerous challenges. This study introduces a method that combines laser scanning and photographic measurements to digitize precisely nonstandard elements of rockery stones. This approach presents an innovative design and construction workflow for rockeries by refining design processes, showcasing real effects, and resolving assembly issues. The results demonstrate that the combination of three-dimensional laser scanning and close-range photogrammetry can accurately replicate the complex forms and textures of these nonstandard elements. The stone coding and digital management system devised based on the logic of construction effectively satisfies the design and building requirements of rockeries. Correspondingly, the proposed digital construction workflow enhances the accuracy of rockery design, presentation, and evaluation, thereby contributing to the protection and restoration of rockery heritage sites and the transmission of rockery construction techniques.

Diagnostic reproducibility of the 2018 Classification of Gingival Recessions: Comparing photographic and in-person diagnoses.

To assess how the diagnostic reproducibility of the 2018 Classification of Gingival Recession Defects (GRD) could be applied when comparing in-person chairside measurements with photographic measurements. Thirty-four GRD were photographed and evaluated by 4 masked operators. For each case, the operators measured twice recession type (RT), recession depth (RD), keratinized tissue width (KTW), gingival thickness (GT), detectability of the cemento-enamel junction (CEJ), and presence of root steps (RSs), chairside, and on photographs. Intraclass correlation coefficient (ICC) with 95% confidence intervals (CI) was calculated for RD and KTW; Kappa with 95% CI was used for GT, CEJ, and RS; quadratic weighted Kappa with 95% CI was used for RT. RD, KTW, and RT showed excellent overall intra-operator agreement (>0.93), and from good to excellent overall inter-operator agreement (>0.80), for both clinical and photographic measurements. Agreements were lower for GT, CEJ, and RS. Overall clinical and photographic agreements were within 0.1 difference for every variable, except for inter-operator agreement for RS which was 0.72 for clinical measurements and 0.45 for photographic measurements. The lowest overall agreement between clinical versus photographic measurements existed for CEJ (0.28) and RS (0.35). Variables composing the 2018 Classification of GRD are reproducible, both clinically and on photographs, with comparable agreements. The overall agreement was higher for KTW, RD, and RT, and lower for GT, CEJ, and RS, for both clinical and photographic measurements. The comparison between chairside and photographic evaluations indicated fair to excellent agreement for most variables, with CEJ and RS showing fair agreement. As digital diagnostics evolve to facilitate clinical diagnostic measurement, we aimed to assess the effectiveness of intraoral photography for diagnosing gingival recession defects (GRD) according to the 2018 Classification of GRD, compared to traditional clinical examination. Standardized photographs of thirty-four GRD cases were captured. Four masked operators evaluated the same gingival recessions twice in a clinical setting and twice using photographs. Measurement repeatability within and between operators was calculated for both clinical and photographic settings, and the two settings were compared. Continuous measurements such as recession depth and keratinized tissue width, as well as the evaluation of interproximal attachment height (recession type), showed excellent agreement both clinically and photographically. Agreement was lower for gingival thickness and the detectability of tooth anatomical landmarks, such as the cemento-enamel junction and the presence of root steps. Overall, the agreement between chairside and photographic evaluations was generally good, but lower when evaluating tooth anatomical landmarks. The variables composing the 2018 Classification of GRD are reproducible in both clinical and photographic settings, with comparable levels of agreement. However, there was consistently worse agreement for gingival thickness and when evaluating tooth anatomical landmarks.

To compare horizontal strabismus deviation as assessed from photographs with that in the strabismus clinic using the prism bar.

To compare the deviation in cases of horizontal strabismus as assessed from photographs with the measurements as obtained in the strabismus clinic. After obtaining informed consent, we recruited subjects with manifest horizontal strabismus. We took a frontal flash photograph from a distance of 50 cm using smart-phone-based cameras with the flash light vertically aligned with the lens. After projecting the photograph on a laptop and using a vernier caliper, we measured the horizontal corneal diameter of the non-strabismic eye and the decentration of reflex in the strabismic eye taking limbus as the reference point. We converted these values to degrees by using a conversion factor of 7.5°/mm and further to prism diopters (PD) by the standard mathematical formula 100*tanθ. We included 74 subjects aged between 5 and 40 years with manifest horizontal deviation from 20 to 85 PD. We found a statistically significant correlation of 82.6% (P value < 0.001) between the clinic and photographic measurements. Agreement analysis suggested that the photographic measurements measured on average 7 PD less (95% confidence interval: 4.6 to 9.2) than clinical measurements along all values of misalignment, although the difference between the two methods decreased as the quantum of deviation increased. Linear regression revealed an r2 of 68% and provided a predictive equation to derive clinic equivalent measurements from photographic estimates. We believe our simple method provides robust evidence that a photographic estimation can provide the basic information of the size of the deviation to plan possible surgeries, especially in situations of a tele-consultation. This is an easy approach to both understand and master and should form the armamentarium of most orthopticians and strabismologists.

Investigation of muscle activation during kinetic chain based exercises in individuals with and without forward head posture.

The Band Pull-Apart (BPA) exercise is used to strengthen the periscapular muscles. It was recently stated that the lower extremity and trunk movements should be included in the shoulder rehabilitation programs to optimize an effective energy transfer throughout the kinetic chain. The aim of this study is to investigate the effects of kinetic chain based BPA exercise on the muscle activations of the sternocleidomasteideous (SCM) and the trapezius muscles in individuals with and without forward head posture (FHP). Eighteen individuals with FHP and 18 individuals without FHP were included. Photographic measurements were made to identify individuals with FHP. The muscle activations of SCM, Upper Trapezius (UT), Middle Trapezius (MT), and Lower Trapezius (LT) were measured with surface EMG. BPA exercise was performed in the standing, unipedal standing, squat, unipedal squat, and Bulgarian split squat (BSS). There was no Group × Exercise interaction for the SCM, UT, MT, LT muscle activations, or for the UT/MT and UT/LT ratios (p> 0.05). While there was a difference in the activation of all muscles between individuals with and without FHP (p< 0.05), both ratios were similar (p> 0.05). There was a statistically significant difference between exercises for SCM, MT, and LT muscle activations (p< 0.000 for these muscles), UT/MT (p< 0.000) and UT/LT ratios (p= 0.004). SCM muscle activation in squat was lower than activation in standing (Mean Difference (MD) = 2.5% Maximal Voluntary Isometric Contractions (MVIC); p= 0.004) and in unipedal standing (MD = 2.1% MVIC; p= 0.002). MT muscle activation in squat was higher than activation in standing (MD = 9.7% MVIC), unipedal standing (MD = 7.8% MVIC), unipedal squat (MD = 6.9% MVIC) and BSS (MD = 9.4% MVIC; p< 0.000 for these positions). LT muscle activation in the squat was higher than activation in the standing (MD = 8.5% MVIC) and unipedal squat (MD = 8.1% MVIC; p< 0.004 for these positions). UT/MT ratio in the squat was lower than standing (MD = 0.3), unipedal standing (MD = 0.2) and BSS (MD = 0.3; p< 0.000 for these positions). UT/LT ratio in squat was lower than unipedal squat (MD = 0.5) and BSS (MD = 0.6; p= 0.002; for these positions). Performing the BPA exercise in the squat position is suggested in cases where lower SCM and UT muscle activation, lower UT/MT, and UT/LT ratios and higher MT and LT muscle activations are needed for individuals with and without FHP.

Forward Head Posture and Its Effect on Muscle Activation

Forward head posture (FHP), which is defined as a forward displacement of the head on the cervical spine, is a common postural disorder. It is suggested that this malalignment alters the loads on the spine, affects the length-tension relationship in muscles, and changes muscle activation. Therefore, the aim of this review is to investigate the results of studies on the examination of the changes exerted by FHP on muscle activation. Although there are many methods used to assess FHP, there is no standard clinical method for accurate measurement of this angle. Photographic measurement is the most widely used, valid, and reliable assessment method. Craniovertebral angle (CVA) is the most widely used value to assess FHP in photographic measurements. A CVA of less than 48-50° is defined as FHP, although there are differences regarding the norm value of the CVA. There are many studies on the assessment of differences in the activation of the neck and shoulder muscles by making FHP and non-FHP classifications according to the CVA to show the changes in muscle activation in individuals with FHP. Although many studies have shown increased sternocleidomastoideus and upper trapezius activation, there are also others indicating no difference. Similar conflicting results exist for the lower trapezius and serratus anterior muscles. Although there are conflicting results regarding muscle activation in studies, it seems likely that muscle activation is altered in individuals with FHP. It may be recommended that physiotherapists conduct interventions by considering these differences in muscle activation in individuals with FHP.

Measuring coral disease lesions: a comparison of methodologies

The presence of stressors, particularly disease, on corals necessitates assessments of their severity in order to compare threat levels and to plan for impacts. Diseases in particular are often measured via the rate at which a lesion moves across a coral (lesion progression rate) to determine the impact of those lesions and also to compare virulence across species, regions, and disease types. Lesion progression can even be used as a field indicator for disease identification. Many different methodologies have been used to measure lesion progression rates. These may be field-based or photographic measurements, and they include linear progression rates as well as areal progression rates. All methods have pros and cons, including varying levels of accuracy and repeatability, variability with respect to colony and lesion sizes, and time and computational requirements. Additionally, not all metrics can be directly compared, and so experiments done with the intent to compare with previous work must consider methodologies used in former studies. Areal progression rates have high variability, but can provide impressive information on overall tissue loss. Overall, linear lesion progression rates provide more accurate and less variable assessments of loss, and are better used for comparisons. Using the average of multiple linear measurements may further increase precision. Measuring from photographs rather than direct field measurements provides a more permanent and repeatable record, but outside of directly planar surfaces is likely to yield inaccuracies. The emerging use of 3-D photogrammetry can overcome many of these limitations, but the methods require considerable time and computational power. The pros and cons of each methodology should be assessed during experimental design to best answer the hypotheses in question as well as consider whether comparisons to other studies are valid.

Improvement of photogrammetric joint roughness coefficient value by integrating automatic shooting parameter selection and composite error model

In order to improve the accuracy of the photogrammetric joint roughness coefficient (JRC) value, the present study proposed a novel method combining an autonomous shooting parameter selection algorithm with a composite error model. Firstly, according to the depth map-based photogrammetric theory, the estimation of JRC from a three-dimensional (3D) digital surface model of rock discontinuities was presented. Secondly, an automatic shooting parameter selection algorithm was novelly proposed to establish the 3D model dataset of rock discontinuities with varying shooting parameters and target sizes. Meanwhile, the photogrammetric tests were performed with custom-built equipment capable of adjusting baseline lengths, and a total of 36 sets of JRC data was gathered via a combination of laboratory and field tests. Then, by combining the theory of point cloud coordinate computation error with the equation of JRC calculation, a composite error model controlled by the shooting parameters was proposed. This newly proposed model was validated via the 3D model dataset, demonstrating the capability to correct initially obtained JRC values solely based on shooting parameters. Furthermore, the implementation of this correction can significantly reduce errors in JRC values obtained via photographic measurement. Subsequently, our proposed error model was integrated into the shooting parameter selection algorithm, thus improving the rationality and convenience of selecting suitable shooting parameter combinations when dealing with target rock masses with different sizes. Moreover, the optimal combination of three shooting parameters was offered. JRC values resulting from various combinations of shooting parameters were verified by comparing them with 3D laser scan data. Finally, the application scope and limitations of the newly proposed approach were further addressed.

Numerical and experimental investigation on crack detection in a beam using maximal overlapping discrete wavelet transform

The present study is concerned with detecting a crack in the beam numerically and experimentally using maximal overlapping discrete wavelet transform (MODWT). Slope discontinuity in the beam elastic line can reveal the presence of a crack in a beam. The MODWT is used for locating the cracks in a beam. MODWT coefficients are compared with discrete wavelet transform coefficients at different noise levels. For the experimental validation, high-resolution measurements of the cantilever beam deflection are obtained using photographic measurements. The algorithm is tested for the detection of cracks away and near the ends of a beam. Crack detection near the end of the beam is difficult due to border distortion. Border distortion suppresses the signal in that region. Isomorphism is utilized to shrink the border distortion zone. It helps in the better visualization of the spike due to the crack located away from the ends. Moving averaging is applied to the MODWT-based results for better localization of the spike near the crack position.

Fundus torsion following inferior oblique muscle weakening

PurposeTo determine the postoperative fundus torsion following surgical inferior oblique (IO) weakening in patients with inferior oblique overaction (IOOA). MethodsIn this interventional case series, 37 patients with IOOA ≥ +1 and reliable preoperative fundus photographs were included. IO weakening was accomplished through myectomy or anterior transposition. Fundus photography was repeated at 3 months’ follow-up. The primary outcome was change of disk foveal angle (DFA), measured as the angle between the line connecting the center of the fovea and optic disk and horizontal. Success or normal fundus torsion was defined as a postoperative angle of 0° to 8° of extorsion. Residual extorsion was defined as postoperative extorsion of > 8°. Postoperative intorsion was defined as any amount of induced intorsion. ResultsMean age of patients (56% females) was 6.46 ± 6.79 years. At follow-up at least 3 months after surgery, the mean change of DFA was 7.79 ± 6.24° of reduction of extorsion after IO myectomy (P < 0.001) and 6.05 ± 6.07° after IO anterior transposition (P = 0.005). Normal fundus torsion was achieved in 50% of patients after myectomy and 36.4% of patients after anterior transposition. Residual extorsion was observed in 49% of patients; induced intorsion in 5%. ConclusionsUsing objective measurement of fundus photographs, fundus extorsion was decreased in 94.7% of patients after myectomy or anterior transposition.

The Effect of the Lateral First Metatarsal Head Shape on Hallux Valgus in Forced Turnout in Pre-Pointe Female Ballet Dancers: A Pilot Study.

A rounded lateral first metatarsal head shape is associated with higher rates of hallux abducto valgus recurrence following corrective surgery; however, the effect of the lateral first metatarsal head shape on the hallux abduction angle (HAA) has not yet been explored in a nonpathologic, pre-pointe ballet dancer population. The primary purpose of this study was to investigate the effect of the lateral first metatarsal head shape on the HAA when pre-pointe female dancers force their turnout. Seventeen female, pre-pointe ballet students (mean age, 10.8 ± 0.95 years) participated in this study. Fluoroscopic images of each dancer's dominant foot were taken, and the lateral first metatarsal head shape was classified visually. Each dancer performed three consecutive stances of natural double-leg upright posture: both functional and forced turnout. HAAs were obtained by marking medial bony landmarks on paper and were compared to photographic measurements. No significant difference was found between the round and angular lateral first metatarsal head shape for the change in HAA from natural double-leg upright posture to forced turnout. Hallux abduction angle significantly increased by 4.6° (P < .001) in forced turnout compared to the natural double-leg upright posture for the photographic method, whereas the paper method demonstrated an increase of 2.6° (P = .007). No statistical differences were found between the paper and photographic methods in measuring the HAA for all stances. Our findings suggest no association between the HAA and lateral first metatarsal head shape; however, HAA does increase when a dancer assumes forced turnout. The paper method demonstrated similar reliability to the photographic method and shows the potential for future use as a clinical tool in assessing hallux abducto valgus.

Correlation between lateral cephalometric and facial photographic measurements for orthodontic diagnosis in patients with mandibular deficiency

Correlation between lateral cephalometric and facial photographic measurements for orthodontic diagnosis in patients with mandibular deficiency

Evaluation of the Clinical Effect of Hyaluronic Acid Mouthwash on Palatal Secondary Wound Healing in Diabetic Rats

Objective: The objective of this study was to investigate clinical effect of topically administered hyaluronic acid (HA) mouthwash on healing of secondary palatal wound in diabetic (D) rats. &#x0D; Methods: 60 Wistar albino male rats were divided into D and non-diabetic (ND) groups. Diabetes was induced to 30 randomly selected rats by initially administering 110 mg/kg of nicotinamide intraperitoneally, followed by 15 min of intraperitoneal injection of 65 mg/kg of streptozotocin solution. 5 mm excisional wounds were made in the centre of the palate. After that, 6 animals from each group were sacrificed. Then, both groups were subdivided into two groups: 0.12% HA mouthwash and saline (S) (n=12 per group), depending on the agent to be administered to the wound area (WA). On days 7 and 14, six rats from each group were sacrificed, and the WAs were measured through photographic measurements utilizing Image J software.&#x0D; Results: The WA decreased with time in each group (p

Photogrammetric angular measurements as a diagnostic tool for orthodontic treatment planning

Objectives: The aim of the study was to compare and correlate angular measurements of soft-tissue profile between cephalogram and photograph and to identify gender difference. Materials and Methods: Sample size consisted of 100 lateral cephalograms and 100 profile photographs of 100 Indian Bengali population aged 18– 25 years (50 males and 50 females; mean age = 21.28 years). All records were taken in natural head position, centric occlusion, and lips in relaxed position. For evaluation of method reliability, intra-class correlation coefficients (ICCs) were calculated from repeated photographic measurements. Similarly, cephalometric and photographic measurements were compared for assessing Pearson correlation coefficients. Linear regression analyses were done for the variable with correlation coefficients &gt;r = 0.7. Ten angular parameters were used for soft tissue analysis and t-test was used for comparison. Statistical analyses were done using the Statistical Package for the Social Sciences for Windows software version 21.0. Results: The reliability test for photographs was found satisfactory with most measurements showing ICCs ≥ 0.90 and highly significant correlations (P ≤ 0.001) with cephalometric measurements. The N’-Prn’-Pg’ angle was found most effective for female subjects (r2 = 0.82), the N’-Prn’/N’-Pg’ angle for male subjects (r2 = 0.89) and among total subjects, the N’-Prn’/N’-Pg’ angle (r2 = 0.88). Conclusion: Photographs may be used for soft tissue evaluation for diagnosis and treatment planning as an alternative to cephalometric soft-tissue analysis.

Primary rhinoplasty in patients with bilateral cleft lip: Longitudinal results and comparison between closed and semi-open approaches

Although several studies have shown that primary rhinoplasty in patients with cleft lip provides good outcomes with limited effect on nasal growth, the surgical procedure remains to be standardized. The purpose of this study was to evaluate the long-term outcome of primary semi-open rhinoplasty with Tajima reverse-U incision, compared with that of closed rhinoplasty. Consecutive nonsyndromic patients with complete bilateral cleft lip and palate (n=52) who underwent primary semi-open rhinoplasty between 2001 and 2016 were reviewed. Patients who underwent primary closed rhinoplasty (n=61) and control group individuals were recruited for comparison. Computer-based standardized measurements of 2D photographs and panel assessments by laypersons were collected and statistically analyzed. In the comparative analysis at preschool age, semi-open rhinoplasty significantly improved the typical nasal deformities, including transversely oriented wide nostrils, short columella, and de-projected nasal tip, more effectively than closed rhinoplasty. Without major drawbacks, these parameters in the semi-open group were well maintained closer to those in the control group till skeletal maturity. After primary rhinoplasty, 54% of patients in the closed group and 4% in the semi-open group underwent intermediate rhinoplasty at preschool age. This study showed that the patients who underwent primary semi-open rhinoplasty achieved long-term and persistent outcomes that were closer to the normal nasal morphology compared with the patients treated with closed rhinoplasty, while avoiding intermediate rhinoplasty during the preschool to adolescent periods.

Wound healing of experimental equine skin wounds and concurrent microbiota in wound dressings following topical propylene glycol gel treatment.

Topical wound treatments rely on carrier formulations with little to no biological impact. The potential for a common vehicle, a propylene glycol (PG) gel, to affect wound healing measures including microbiota is not known. Microbiome characterization, based on next generation sequencing methods is typically performed on tissue or directly obtained wound fluid samples. The utility for primary wound dressings to characterize equine wound microbiota in the context of topical treatments is currently unknown. This investigation reports the topical effect of an 80% PG based gel on wound healing and microbiota in wound dressings. Experiments were performed in six mature horses utilizing a surgical, distal limb wound model, histology of sequential wound biopsies, photographic wound measurements and microbiota profiling via 16s rRNA sequencing of wound dressing samples. Experimental wounds were surveyed for 42 days and either treated (Day 7, 14, 21 and 28; at 0.03 ml/cm2) or unexposed to the PG gel. Wound surface area, relative and absolute microbial abundances, diversity indices and histologic parameters were analyzed in the context of the experimental group (treatment; control) using qualitative or quantitative methods depending on data characteristics. Compared to controls, treatment slowed the wound healing rate (17.17 ± 4.27 vs. 18.56 ± 6.3 mm2/day), delayed the temporal decline of polymorphonucleated cells in wound beds and operational taxonomic units (OTU) in wound dressings and lowered alpha-diversity indices for microbiota in primary wound dressing. Relative abundances of OTUs were in line with those previously reported for equine wounds. Clinical outcomes 42 days post wounding were considered similar irrespective of PG gel exposure. Results highlight the potential for vehicle exposure to alter relevant wound outcome measures, imposing the need for stringent experimental control measures. Primary wound dressings may represent an alternate sample source for characterization of the wound microbiome alleviating the need for additional interventions. Further studies are warranted to contrast the microbiome in wound dressings against that present on wound surfaces to conclude on the validity of this approach.

Can intraoral and facial photos predict obstructive sleep apnea in the general and clinical population?

This study aimed to evaluate and compare measurements of standardized craniofacial and intraoral photographs between clinical and general population samples, between groups of individuals with an apnea-hypopnea index (AHI) ≥ 15 and AHI < 15, and their interaction, as well as the relationship with the presence and severity of obstructive sleep apnea (OSA). We used data from 929 participants from Sleep Apnea Global Interdisciplinary Consortium, in which 309 patients from a clinical setting and 620 volunteers from a general population. AHI ≥ 15 were observed in 30.3% of the total sample and there were some interactions between facial/intraoral measures with OSA and both samples. Mandibular volume (p < 0.01) and lateral face height (p = 0.04) were higher in the AHI ≥ 15 group in the clinical sample compared to the AHI ≥ 15 group in the general population and AHI < 15 group in the clinical sample. When adjusted for sex and age, greater mandible width (p < 0.01) differed both in the clinical and in the general population samples, reflecting AHI severity and the likelihood of OSA. The measure of smaller tongue curvature (p < 0.01) reflected the severity and probability of OSA in the clinical sample and the higher posterior mandibular height (p = 0.04) showed a relationship with higher AHI and higher risk of OSA in the general population. When adjusted for sex, age, and body mass index, only smaller tongue curvature (p < 0.01) was associated with moderate/severe OSA. Measures of greater tongue and mandible were associated with increased OSA risk in the clinical sample and craniofacial measurement was associated in the general population sample.

Comparison of angular measurements in cephalometrics and photographs.

Abstract:&#x0D; Introduction: The evaluation of the facial profile is an important factor in any current orthodontic diagnosis and accurate treatment planning is dependent on it.&#x0D; Aims and Objectives: The aim and objective of the study is to find out differences in angular measurements between photographic and cephalometric measurements whether photographic measurements can be used in place of cephalometric measurements.&#x0D; Material &amp; Methods: The study comprised 100 volunteers (50 males and 50 females) ranging in age from 12 to 16 years. The respondents were chosen at random throughout the sampling process. Cephalometric and photographic profile analysis was used, with angular measurements based on standard cephalometric and photographic records taken in natural head position in lateral view. Lateral cephalogram was used for cephalometric analysis and photograph taken in lateral view was used for evaluation. The study included four factors in total.&#x0D; Results: There was no significant difference in facial angular measurements between the cephalometric and photographic analysis.&#x0D; Conclusion: This study concluded that photographic measurements can be used in place of lateral cephalogram as there are negligible differences between them&#x0D; Keywords: Photographic analysis, Cephalometric analysis, Naso-labial angle, Naso-mental angle, Naso-frontal angle, Naso-facial angle

Fault Diagnosis of the LAMOST Fiber Positioner Based on a Long Short-term Memory (LSTM) Deep Neural Network

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) has been in normal operation for more than 10 yr, and routine maintenance is performed on the fiber positioner every summer. The positioning accuracy of the fiber positioner directly affects the observation performance of LAMOST, and incorrect fiber positioner positioning accuracy will not only increase the interference probability of adjacent fiber positioners but also reduces the observation efficiency of LAMOST. At present, during the manual maintenance process of the positioner, the fault cause of the positioner is determined and analyzed when the positioning accuracy does not meet the preset requirements. This causes maintenance to take a long time, and the efficiency is low. To quickly locate the fault cause of the positioner, the repeated positioning accuracy and open-loop calibration curve data of each positioner are obtained in this paper through the photographic measurement method. Based on a systematic analysis of the operational characteristics of the faulty positioner, the fault causes are classified. After training a deep learning model based on long short-term memory, the positioner fault causes can be quickly located to effectively improve the efficiency of positioner fault cause analysis. The relevant data can also provide valuable information for annual routine maintenance methods and positioner designs in the future. The method of using a deep learning model to analyze positioner operation failures introduced in this paper is also of general significance for the maintenance and design optimization of fiber positioners using a similar double-turn gear transmission system.

Preliminary Results of Measurements of Frontal Plane Knee Alignment Using a Standardized, Sonographic-Assisted Digital Photograph—A Reliable and Accurate Alternative to a Full-Leg Radiograph?

(1) Clinical alternatives to the full-leg radiograph (FLR) for determining frontal plane lower limb alignment have shown mixed results so far concerning reliability and accuracy. In addition, intercondylar respectively intermalleolar distance (ICD/IMD) measurement is limited in the interpretation of its results. The purpose of the study is to present a standardized, sonographic-assisted photographic measurement (SPM) of the leg axis in the frontal plane using a digital photograph and compare it with the gold standard of the anterior–posterior FLR. (2) Adults who had recently received an FLR were included in the study. After determining the center of the hip joint and knee joint gap in a standing position via ultrasound, a standardized digital photograph was taken. Subsequently, the hip–knee–ankle angle (HKA) was measured using an image editing program for SPM and FLRs. Mean deviation (MD), Pearson’s correlation coefficient and the clinical method’s interclass correlation coefficient (ICC) were calculated. (3) Of 18 subjects (8 male and 10 female), respectively, 34 lower extremities have been included in the study. Their mean BMI was 25.5 kg/m2. The correlation between the two measurement methods for subjects with BMI &lt; 30 kg/m2 was reliably high (r = 0.93, p &lt; 0.001). The HKAs derived from SPM and FLRs showed a mean deviation (MD) of 2.4° (range 0.1–6.0°) for subjects with BMI &lt; 30 kg/m2. The average ICC among all examiners conducting the SPM was 0.99 (CI 0.95–0.99, p &lt; 0.001). The MD for subjects ≥ 30 kg/m2 increased significantly (MD = 5.5°; n = 10, p &lt; 0.001). (4) SPM of the leg axis in the frontal plane allows sufficiently accurate results in patients with a BMI lower than 30 kg/m2. The methodology is limited in cases of increased BMI and needs well-trained examiners. Nevertheless, as a screening method in the field of children and adolescents, this method can be recommended in clinical daily routine.